What is the cause of my aunt's pain?

Menstruation shows lumbago, more consideration is the following reasons: the first is during menstruation prostaglandin secretion increased will cause uterine contraction pain, and then cause some lumbago; The second is to eat some cold food during menstruation, but also cause lumbago; The third is during menstruation, some people cervical canal is too tight or uterine position is too backward, which will cause menstrual blood flow is not smooth, uterine contraction increased will cause dysmenorrhea, some will also show lumbago; The fourth is that some people take a cold bath during menstruation, so that the uterus will also cause menstrual blood stasis, causing dysmenorrhea to radiate to the lumbosacral region causing low back pain.